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So, I'm having this ongoing battle with Joe's 164, an '89 V6, manual.
When cold the engine idles nicely. When warm the idle speed is around 1000RPM. It idles smoothly and drives smoothly.
Unplugging the idle air valve causes a stutter, then increases the idle speed further.
I have put several turns of tape around the grommet and made the clamp a tight fit.
Unplugging the throttle switch increases the idle speed, so that is also set correctly.
I have pulled off the chrome pipes and found leaky gaskets. I refitted the pipes several times with different sealants. Spraying brake cleaner around them caused a stutter. Eventually I removed the fuel rail and repaired stripped threads for the chrome pipes. Cleaned everything up and fitted new gaskets, new bolts. Spraying brake cleaner around no longer causes a stutter, engine runs a little smoother. Still no change to hot idle speed.
Never had this problem until I cleaned the throttle body. Throttle stop screw is backed right off and throttle cable is slack. If I press the throttle plate HARD closed, idle speed drops.
Also cleaned and refixed pipes for oil vapour separator. Removed and inspected corrugated pipe and refitted with great care to ensure all pipes fitted tightly with new clamps. No change.
Tried removing/plugging lines to brake servo and fuel pressure regulator. No change. Even replaced oil filler cap and dipstick O-rings in case air being drawn through crankcase.
Going to try a spare idle air valve and slacken/retighten throttle plate screws. Also thinking of swapping throttle body for spare but I can't see that making much difference, I didn't think the throttle had to be pushed so completely closed.
Running out of patience and ideas, any advice welcomed!
Thanks for reading,
-Alex
When cold the engine idles nicely. When warm the idle speed is around 1000RPM. It idles smoothly and drives smoothly.
Unplugging the idle air valve causes a stutter, then increases the idle speed further.
I have put several turns of tape around the grommet and made the clamp a tight fit.
Unplugging the throttle switch increases the idle speed, so that is also set correctly.
I have pulled off the chrome pipes and found leaky gaskets. I refitted the pipes several times with different sealants. Spraying brake cleaner around them caused a stutter. Eventually I removed the fuel rail and repaired stripped threads for the chrome pipes. Cleaned everything up and fitted new gaskets, new bolts. Spraying brake cleaner around no longer causes a stutter, engine runs a little smoother. Still no change to hot idle speed.
Never had this problem until I cleaned the throttle body. Throttle stop screw is backed right off and throttle cable is slack. If I press the throttle plate HARD closed, idle speed drops.
Also cleaned and refixed pipes for oil vapour separator. Removed and inspected corrugated pipe and refitted with great care to ensure all pipes fitted tightly with new clamps. No change.
Tried removing/plugging lines to brake servo and fuel pressure regulator. No change. Even replaced oil filler cap and dipstick O-rings in case air being drawn through crankcase.
Going to try a spare idle air valve and slacken/retighten throttle plate screws. Also thinking of swapping throttle body for spare but I can't see that making much difference, I didn't think the throttle had to be pushed so completely closed.
Running out of patience and ideas, any advice welcomed!
Thanks for reading,
-Alex